Improvement in tripods for rock-drills



T. B. FORD.

TmPons Fon nocK-nnILLs. Y No. 189,853, f Patented Apr11z4,1 a77 UNVENT1RQ MFEVERS, lHOTO-LhTHOGHAPHERv WASHINGTON, D,

n UNITED STATES PATENT QEEIOEc THOMAS B. EOBD, OE NEwBUEG, NEW YORK.

IMPROVEMENT IN TRIPODS F'OR ROCKrDRILLS.

Specification forming part of Letters Patent No. 189,853, dated April 24, 1877; application filed i March 7, 1877.

To all whom it may concern Beit known that I, THOMAS B. FORD, of

ends, in which arms are adjustable and firmly held by means of concave Washers fitted to the circumference ofthe bar, and keys. These varms may be fastened in any part of the grooves. By rounding the outer surface of the projections on the arms, and forming the grooves of a similar shape to receive them, with'play in the slots on the surface of the bar, the arms may be moved sidewise for adjustment.

The bar may be made of plain cylindrical form, or with a head of spade-handle shape, or any other desired form, to receive the machine. The weights to steady the tripod are movable radially on the arms, and may be held by keys or set-screws, or may be Iirmly attached thereto. The points on which the tripod stands are bars pointed at their lower ends, liattened and tapered toward the upper ends, and adjustable in and through slots in the weights by keys or otherwise.

A is the upper part of the bar; B, the lower part; C, its center. The bar may be provided with one or two sets of grooves, Hl H2 H3, increasing in depth from the lower part upward. The arms Fl F2 F3 are flat, with the ends fitting in the undercut grooves, the opening slot in the surface of the bar being wider than the arms, so that the arms can swing in the slots, as indicated by arms F4 and F5 in Fig. 2. By driving the key K through the slot in the arm and against the washer W, the arm F is held firmly in the undercuts. the weights, of which thereis one for each arm, provided with slots Nl N2 to receive the arm F1, on which the Weight is adjustable radially, as shown in Fig. 2, drawn in full and dotted lines, and is also reversible. Near one end of the weight is the slot g g, to receive the point G. These are rods pointed at the lower ends, flattened and tapered toward the upper end, and t loosely inthe slots, which increase in size towardV both ends to allow the points to swing for the purpose of adjusting them. Said rods may be held by a key or setscrew.

What I claim as my invention, and desire to secure by Letters Parent, B

1. In a tripod, a round vertical bar, A B, provided with longitudinal undercut grooves H, in combination with arms F, movable therein, and radially-adjustable weights P and points G, substantially as specified.

2. In a tripod, the radial arms F, vertically adjustable in undercut slots, in combination with the radially adjustable and reversible weights P, withA adjustable swinging points G, as specified. y

3. In a tripod, a 'single vertical round bar, A B, with longitudinal undercut grooves, in combination with a horizontal bar, substantially as specied.

THOS. B. FORD. Witnesses:

T. W. GEEEGKE, ALEX. J. BLITT.

P represents one ofl 

